Latch mechanism



Jan. 17, 1961 K. H. LADE LATCH MECHANISM 4 Sheets-Sheet 1 Filed Sept.18, 1958 "Jill bL| INVENTOR. XAFL H Z/lfif ATTOKA/EX Jan.

Filed Sept. 18, 1958 K. H. LADE LATCH MECHANISM 4 Sheets-Sheet 2 Jan.17, 1961 K. H. LADE LATCH MECHANISM 4 Sheets-Sheet 3 Filed Sept. 18,1958 INVENTOR. KAAZ H Z4D 040% Jan. 17, 1961 Filed Sept. 18, 1958 K. H.LADE LATCH MECHANISM 4 Sheets-Sheet 4 flyjd INVENTOR. KAtL H 1/10;

United States Patent The doors of walk-in refrigerators and otherenclosures must be kept tightly closed at all times and, for obviousreasons, such doors must be capable of being opened from within theenclosure. A satisfactory latch of this type is shown in Patent No.1,752,131 issued to G. P. Wild on March 25, 1930.

One object of the invention is to produce an improved latch mechanism ofthis type.

A further object is to produce an improved latch mechanism of the typeset forth which is also capable of being opened from the inside evenwhen the latch mechanism is locked and cannot be opened from theoutside.

As far as I am aware, doors of the type referred to have been providedwith a single latch mechanism located substantially midway of the heightof the door opening. Such an arrangement is satisfactory when used on arelatively small door. But, in the case of a relatively large door, theupper and lower corners of the door were not closed sufficiently tightlyand, in time, the door tended to warp. This disadvantage increased withthe increase in the vertical dimension of the door opening. Nor is itpractical to provide two or more vertically spaced, individuallyoperable, latches because it would be necessary separately to operateeach of said latches every time the door is opened and closed.Furthermore, a latch mechanism placed near the upper edge of arelatively large door will be inaccessible from the floor without theuse of a stool or ladder which has heretofore made the use of multiplelatch mechanisms still more impracticable.

It is therefore a still further object of the invention to produce amultiple latch mechanism which includes an upper unit and a lower unitfor acting on the upper and lower portions of the door, with, orwithout, a unit for acting on an intermediate portion of the door.

A still further object is to produce a latch mechanism which embodiesthe improvements referred to, but which is durable and easy to make,install and operate and one which is tamper proof.

A still further object of the invention is to produce an improved latchmechanism, the cooperating parts of which can be readily assembled toform a single unit for acting on a single portion of the door and whichcan also be readily assembled to produce a multiple latch mechanismincluding two, or three units for acting on the top and bottom portionsof the door alone, or on the upper, lower and central portions of thedoor simultaneously.

The full nature of the invention will be understood from the followingspecification and the accompanying drawings in which Fig. 1 is a frontelevational view of a door provided with one latch mechanism embodyingthe invention.

Fig. 2 is an enlarged sectional view taken on line 2-2 on Fig. 1.

Fig. 3 is a much enlarged view partly in front elevation and partly invertical section showing various parts of the latch mechanism.

Fig. 4 is a sectional view taken on line -,4 on Fig. 3. Fig. 5 is asectional View taken on line 5-5 on Fig. 3. Fig. 6 is a sectional viewtaken on line 6-6 on Fig. 3. Fig. 7 is a sectional view taken on line7-7 on Fig. 3. Fig. 8 is a sectional view taken on line 8-8 on Fig. 3.Fig. 9 is a front elevation view of a multiple latch mechanism whichalso includes upper and lower units which act on the top and bottomcorners of the door and which are operated simultaneously with theoperation of the unit which acts on the center portion of the door.

Fig. 10 is a sectional view taken on line 10-10 on Fig. 9.

Fig. 11 is a sectional view taken on line 11-11 on Fig. 9.

Fig. 12 is similar to Fig. 3, but shows an embodiment of the inventionin which the latch mechanism also acts on the top and bottom portions ofthe door.

Fig. 13 is a sectional view taken on line 13-13 on Fig. 12.

Fig. 14 is a sectional view taken on line 14-14 on Fig. 12.

Fig. 15 is a sectional view taken on line 15-15 on Fig. 12.

Fig. 16 is a sectional view taken on line 16-16 on Fig. 12.

Fig. 17 is a sectional view taken on line 17-17 on Fig. 12.

Fig. 18 is a sectional view taken on line 18-18 on Fig. 9.

The embodiment illustrated in Fig. 1 includes a door frame 10 providedwith an opening adapted to be closed by a door 12, mounted on hinges 14.

The door is provided with a substantially centrally located latchmechanism, one part of which is carried by the door frame and the otherpart of which is carried by the door. The part of the latch mechanismcarried by the door frame includes a housing 16 which is suitablysecured to the door frame adjacent the free edge of the door andencloses a tongue 18 which is normally biased by a spring 20 to theright, as viewed in Figs. 1, 2 and 4, or into engagement with the edgeof the door to prevent opening of the door as hereinafter more fullyexplained.

The part of the latch mechanism which is carried by the door includes acasting 22 which is suitably secured to the door by screws 23, or thelike, and which carries spaced, vertically aligning, pairs of bosses 24and 26, and 28 and 30. Also can-ied by casting 22, or by door 12, is anarm 32 which is provided with a flat outer surface 34, which is engagedby tongue 18 when the door is closed, and also with an inner cam surface38 which rides on the cam surface of tongue 18 during the closing of thedoor.

Bosses 28 and 30 have registering openings therein for receiving pivotpin 38 on the upper portion of which, as viewed in Figs. 1 and 2, ispivoted the front end 49 of an operating handle 42. Also pivoted on thelower portion of pin 38 is a lever 44, one end of which is provided witha cam surface 46, which coacts with the cam surface of tongue 18 and theother end of which is provided with an upward extension 48 which abutsor is located in the path of movement of, handle 42 as best shown inFigs. 4 and 5. By this arrangement, rotation of handle 42 in clockwisedirection, as viewed in Fig. 2, or toward the operator as viewed inFigs. 1 and 3, will rotate lever 44 on pivot pin 38 clockwise direction,as viewed in Fig. 4 to push tongue 18 out of the way, or to the positionshown in Fig. 2, in which the door can be opened.

In order to prevent unauthorized opening of the door, a pin 50 isinserted through the openings in the bosses 24 and 26, and its lower endis engaged by the padlock '52, Fig. 3. In this position, pin 50 willabut the outer surface of handle 42 and will prevent movement thereof indoor opening direction, Fig. 2.

In order to prevent tampering, I enclose the parts of the latchmechanism carried by the door with a cover 54; I provide the upper andlower walls of the cover with openings 55 which register with theopenings in bosses 24 and 26, and I pass pin 50 through the openings 55and through the openings in bosses 24 and 26 before applying thepadlock, as best shown in Figs. 3 and 8. By this arrangement, pin 50locks cover 54 and prevents movement of handle 42..

In order to permit opening the door from within, I provide pin 56 whichpasses-through an opening in the door to engage the end 57 of lever 44and rotate it in door-opening, direction, It will be noted that lever 44is rotatable independently of handle 42 so that, by means of pin 56, thedoor can be opened even when padlock 52 is in position and handle 42 isfully immobilized.

The embodiment of Fig, 9 includes top and bottom latch mechanisms whichmay be used in addition to, or in lieu of, the central latch mechanismof Fig. 1. The top and bottom latch mechanisms are identical andtherefore a description of the structure of either of them will sufiice.Also, in describing, the embodiment of Fig, 9, only such parts thereofas are not present in the embodiment of Fig. 1 willv be referred to bynew reference numerals. All other parts will be designated by the primeof the numerals. used in describing the embodiment of Fig. 1.

As best shown inFig. 18, each of the top and lower corner latchmechanisms includes a tongue 18' carried by door frame 10" and remotelyoperable actuating means for pushing tongue 18' out of the way to permitopening of the door. The actuating means referred to includes a pin 60which is freely slidable in openings formed in bosses 62 and is normallybiased away from tongue 18 by a spring 64. Bosses62 are carried by. acasting 22 which corresponds to casting 22.

Pin 60 is urged into engagement with tongue 18 by means of a finger 66which is keyed at 68 to rod 70 whereby rotation of rod 70 in clockwisedirection, as viewed in Fig. 18, will rotate finger 66 into engagementwith pin 60. Rotation offinger 66 causes pin 60 to push tongue, 18', outof engagement with the door. Rod 70 may be an extension of pivot pin 38of Fig. 2, or itmay be a separatepiece keyed to pin 38 as at 72, Fig.15. It is merely necessary that lower rod 70 and its counter part, upperrod 7 4, rotate upon rotation of pivot pin 38 which, in turn, may bemoved by handle 42' fromwithout, or by release pin 56 from within theenclosure.

To present unauthorized opening of the upper and lower latches byrotation of rods 70 and 74 by means of a wrench, or the like I enclosesaid rods with freely rotating tubes 76 as best shown in Figs. 9 and 15.The other parts of the upper and lower latch mechanisms are protectedagainst tampering by covers 54 and padlocks 52 or otherwise.

Release pins 56 and 56? are provided with lever operating handles 78 and78' to provide the mechanical advantage needed to overcome inertia andfriction.

In both embodiments, levers'44 and 44 are biased to the positions ofFigs. and ,13 by springs 80 and 80' respectively.

The operation is as follows:

Rotation-of lever 44, by handle 42 or by release pin 56,

disengages the central latch mechanism, and in the absence of the topand bottom latch mechanisms, the door can be opened.

When the installations include upper and/ or lower latch mechanisms,rotation of lever '44 also rotates upper and/ or lower rod and 74 torotate fingers 66 and push the corresponding tongues 18 out ofengagement with the door.

In order to make the parts interchangeable, lever 44 is keyed to pivotpin 38 so that this sub-assembly can be used interchangeably in bothembodiments.

If it is desired to omit the central latch mechanism, it is merelynecessary to omit tongue 18, casing 16 and to close end of casing 54which faces frame 10.

It will thus be seen that I have provided a latch mechanism which can beused to lock the central portion of the door or which, by adding rods 70and 74 and the upper and lower latch mechanisms, can be used to lock thedoor at two or more points and that the upper and lower latch mechanismsare operated from the central latch mechanism which is readilyaccessible from the floor.

What I claim is:

1. A latch releasing mechanism for a latch carried by the jamb of adoor, said latch releasing mechanism comprising a horizontally disposedtongue carried by the vertical frame which defines the door opening,means biasing said tongue to a first position in which it overlaps theadjacent edge of said door to prevent opening of said door and actuatingmeans for moving said tongue to a second position in which it is out ofengagement with and permits the opening of said door, said actuatingmechanism including a pivot carried by said door near said edge, ahorizontally disposed lever carried by said pivot with one end thereofengageable with said tongue and operable upon rotation on said pivot tomove said tongue to its second position, a handle having one end thereofcarried by said pivot with a portion of said handle located between theother end of said lever and said door, whereby rotation of said handlein one direction about said pivot engages said portion of said handlewith said other end of said lever to rotate said lever in a direction tomove said tongue to its second position, and means operable from theother side of said door for rotating said lever in said directionindependently of said handle.

2. The structure recited in claim 1 and a second tongue mounted adjacentanother portion of the edge of the door, said second tongue beingsubstantially identical with said first tongue in structure and inoperation, a pin mounted in alignment with said second tongue andmovable into and out of engagement with said second tongue, meansnormally biasing said pin out of engagement with said second tongue, acam engageable with said pin and operable, upon being rotated to engagesaid pin with said second tongue to move said second tongue out ofengagement with said door, a rod for rotating said cam, means connectingsaid rod to said pivot, and a sleeve enclosing said rod" and freelyrotatable relative thereto to prevent rotation of said rod except bysaid pivot.

References Cited in the file of this patent UNITED STATES PATENTS1,637,168 Wild July 26, 1927 2,043,787 Wild June 9, 1936 2,631,052Jamison Mar. 10, 1953 2,655,395 Groeger Oct. 13, 1953 2,680,638 GroegerJune8, 1954 2,855,771 Berkowitz Oct. 14, 1958

